| Subject: | Does not correctly recurse into references in a PVNV-type scalar |
I was working on optimizing the memory usage of a program, using
Devel::Size to report on it, when I noticed that a particular change
made for a huge decrease in memory! When I examined it further, I
realized that Devel::Size was sometimes telling me that my hashes were
smaller than their contents.
After much careful analysis with Devel::Peek, I determined that the
problem was this: the nature of my program produced hash values that
were PVNV-types (even though they stored references). When Devel::Size
would go to recurse and find the size of the hash's elements, it doesn't
notice the ROK flag and thus does not recurse into the reference.
The attached file consistently reproduces the problem for me.
******
perl -V output:
Summary of my perl5 (revision 5 version 8 subversion 8) configuration:
Platform:
osname=MSWin32, osvers=5.0, archname=MSWin32-x86-multi-thread
uname=''
config_args='undef'
hint=recommended, useposix=true, d_sigaction=undef
usethreads=define use5005threads=undef useithreads=define
usemultiplicity=define
useperlio=define d_sfio=undef uselargefiles=define usesocks=undef
use64bitint=undef use64bitall=undef uselongdouble=undef
usemymalloc=n, bincompat5005=undef
Compiler:
cc='gcc', ccflags ='-DNDEBUG -DWIN32 -D_CONSOLE -DNO_STRICT
-DHAVE_DES_FCRYPT -DNO_HASH_SEED -DUSE_SITECUSTOMIZE
-DPERL_IMPLICIT_CONTEXT -DPERL_IMPLICIT_SYS -DUSE_PERLIO
-DPERL_MSVCRT_READFIX -DHASATTRIBUTE -fno-strict-aliasing',
optimize='-O2',
cppflags='-DWIN32'
ccversion='12.00.8804', gccversion='3.4.4 (cygming special, gdc
0.12, using dmd 0.125)', gccosandvers=''
intsize=4, longsize=4, ptrsize=4, doublesize=8, byteorder=1234
d_longlong=undef, longlongsize=8, d_longdbl=define, longdblsize=10
ivtype='long', ivsize=4, nvtype='double', nvsize=8, Off_t='__int64',
lseeksize=8
alignbytes=8, prototype=define
Linker and Libraries:
ld='gcc', ldflags ='-nologo -nodefaultlib -debug -opt:ref,icf
-libpath:"C:\Perl\lib\CORE" -machine:x86'
libpth=\lib
libs=-lkernel32 -luser32 -lgdi32 -lwinspool -lcomdlg32 -ladvapi32
-lshell32 -lole32 -loleaut32 -lnetapi32 -luuid -lws2_32 -lmpr -lwinmm
-lversion -lodbc32 -lodbccp32 -lmsvcrt
perllibs=-lkernel32 -luser32 -lgdi32 -lwinspool -lcomdlg32
-ladvapi32 -lshell32 -lole32 -loleaut32 -lnetapi32 -luuid -lws2_32 -lmpr
-lwinmm -lversion -lodbc32 -lodbccp32 -lmsvcrt
libc=msvcrt.lib, so=dll, useshrplib=yes, libperl=perl58.lib
gnulibc_version=''
Dynamic Linking:
dlsrc=dl_win32.xs, dlext=dll, d_dlsymun=undef, ccdlflags=' '
cccdlflags=' ', lddlflags='-mdll'
Characteristics of this binary (from libperl):
Compile-time options: MULTIPLICITY PERL_IMPLICIT_CONTEXT
PERL_IMPLICIT_SYS PERL_MALLOC_WRAP
PL_OP_SLAB_ALLOC USE_ITHREADS USE_LARGE_FILES
USE_PERLIO USE_SITECUSTOMIZE
Locally applied patches:
ActivePerl Build 817 [257965]
Iin_load_module moved for compatibility with build 806
PerlEx support in CGI::Carp
Less verbose ExtUtils::Install and Pod::Find
Patch for CAN-2005-0448 from Debian with modifications
Partly reverted 24733 to preserve binary compatibilty
27528 win32_pclose() error exit doesn't unlock mutex
27527 win32_async_check() can loop indefinitely
27515 ignore directories when searching @INC
27359 Fix -d:Foo=bar syntax
27210 Fix quote typo in c2ph
27203 Allow compiling swigged C++ code
27200 Make stat() on Windows handle trailing slashes correctly
27194 Get perl_fini() running on HP-UX again
27133 Initialise lastparen in the regexp structure
27034 Avoid "Prototype mismatch" warnings with autouse
26970 Make Passive mode the default for Net::FTP
26921 Avoid getprotobyname/number calls in IO::Socket::INET
26897,26903 Make common IPPROTO_* constants always available
26670 Make '-s' on the shebang line parse -foo=bar switches
26379 Fix alarm() for Windows 2003
26087 Storable 0.1 compatibility
25861 IO::File performace issue
25084 long groups entry could cause memory exhaustion
24699 ICMP_UNREACHABLE handling in Net::Ping
Built under MSWin32
Compiled at Mar 20 2006 17:54:25
@INC:
C:/Perl/lib
C:/Perl/site/lib
.
| Subject: | devel-size-broken2.pl |
#!/usr/bin/perl
use Devel::Size qw/total_size/;
my $hash;
$hash->{a} = 0/1;
$hash->{a} = [0..100];
print "Size of hash: ", total_size($hash), "\n";
print "Size of hash's only element: ", total_size($hash->{a}), "\n";